ADAPTIVE CHANGES IN RESPIRATORY PARAMETERS UNDER HIGH-ALTITUDE HYPOXIA: A SYSTEMATIC REVIEW

Abstract

Background: Exposure to high-altitude environments (>2500 m above sea level) subjects the human body to progressive hypobaric hypoxia, triggering a complex series of physiological adaptations primarily orchestrated through the respiratory system. These adaptive responses — spanning ventilatory, hematological, and cellular levels — determine individual tolerance to altitude and underlie the pathophysiology of altitude-related illnesses. Objective: This study aimed to systematically review and analyze the adaptive changes in respiratory parameters occurring under high-altitude hypoxic conditions, with emphasis on the temporal sequence of acclimatization and the physiological mechanisms involved. Methods: A systematic review of 10 peer-reviewed studies published between 2012 and 2024 was conducted, encompassing human field studies, controlled hypobaric chamber experiments, and comparative investigations of lowlander versus high-altitude native populations.